Fuse construction



April 3, 1934-. A, 5, 5 1 E L953f135 FUSE CONSTRUCTION Filed Sept. 3,1932 llgmw J Snvcutor Patented Apr. 3, 1934 PATENT OFFICE FUSECONSTRUCTION Alwin G. Steinmayer, Milwaukee, Wis., assignor to LineMaterial Company, South Milwaukee, Wis, a corporation of DelawareApplication September 3, 1932, Serial No. 631,607

8 Claims.

This invention relates to a construction of fuse, particularly for highvoltage. V

In fuse constructions as heretofore made for use in the protection ofhigh voltage lines it has been the practice heretofore to provide somemeans in certain forms of these fuses for allowingthe fuse to rockoutwardly after the fuse link has been ruptured, to thereby increase theseparation between the live side of the line and 1 the fuse structure.

These devices have heretofore been made either in the form of a sticktype of circuit breaker, which requires a relatively large swing,

or in other types of fuses in which the fuse is located within the tubeopen to the weather at the top. a V

In view of the fact that fiber is the usual, and, in fact, a very highlyserviceable material for the construction of the inner portion at leastof fuse tubes, it has been found that devices of this nature collectwater and the fiber, as is well known, absorbs the water in considerablequantity causing warping and other defects which renders the fuseunserviceable and inoperative.

This invention is designed to overcome the above noted defects, andobjects of this invention are to provide a combined switch and fusewhich is so-made that although a fuse tube is used and is so constructedthat it swings outwardly to provide a wide space between the liveportion of the line and the remainder of the fuse upon rupturing of thefuse link, nevertheless is protected from the collection of water withinthe tube, so that although a fiber tube or at least a fiber lined tubemay be employed, nevertheless warping and distortion and other incidentdefects due to the collection of water is wholly avoided.

In high voltage fuses it is apparent that as these fuses are appliedto-higher and higher voltages, the tubes become increasingly longer sothat the leverage of the pivotally mounted tube increases greatly, andtherefore whenthe fuse drops open under the previous constructions, itis clear that the insulators and associated parts are subjected toincreasing strains. In addition to this defect, it is also well knownthat when a high voltage fuse ruptures, that although the fuse willclear, a metallic coating is formed on the inside wall of the fuse tube.This metallic coating although not being sufficient to necessarily causeinstant leakage and often in no way impairing the operation of the fusetubes on higher voltages, nevertheless results in leakage currentsacross the surfaces of the fuse tube, and also results in a coronadischarge setting up intense radio interfer'ence.

This invention is designed to overcome these defects, and furtherobjects of this invention are 1 to provide a high voltage fuse which isso-made that although a metallic coating may be formed in the fuse tube,that nevertheless a positive gap is always provided when the fuse blowsby the outwardly swinging portion of the fuse structure which bodilymoves away from one of the terminals or live portions of the line, andto so construct the high voltage fuse that although a relatively long orrelatively heavy fuse tube and associated parts may be employed, thatnevertheless no excessive strains are imparted to any portion of themechanism.

Further objects are to provide means for preventing oscillation orswinging of the fuse tube after it has moved outwardly although it maybe acted upon by a high wind, and to provide means which substantiallylocks the fuse in its open position so that there is no repeatedoscillation, even at the instant of operation of the fuse, but insteadin which there is a single outward swing and the tube thereafter lockedin its open position.

Ingreater detail, further objects of this invention are to provide ahigh voltage fuse which may be of the expulsion type. which is pivotedadjacent its upper end, and in which an upper end is set outwardly, fromthe support beyond the lower end, so that the lower end mayswingoutwardly, thereby avoiding any severe shock or stress as might haveoccurred if a fuse, particularly one having a long tube, were pivoted atthe bottom and swung from the top around the bottom pivot.

An embodiment of the invention is shown in the accompanying drawing, inwhich:

Figure 1 is a side view of the structure, with parts broken away.

Figure 2 is a sectional view on the line 2-2 of Figure 1. I 3 Referringto the drawing, it will be seen that the fuse tube is indicated by thereference character 1. This fuse tube may be formed of fiber or may beformed of bakelite or other material provided with a fiber lining, asindicated at2 in Figure 1: The fuse tube carries an upper contact 3 anda lower contact 4.

The upper contact may have a threaded lower portion which receives thethreaded upper end of the fuse tube, and may be of substantiallyrectangular construction adjacent its upper portion, as indicated in thesectional view, Figure 2. 0b-

viously it might also be round without departing from the spirit of thisinvention. At all events, it is provided with a pair of trunnions 5which project outwardly from opposite sides of theupper contact andwhich are received within the hooked ends of the supporting ears orpivot supporting portions 6 of the upper terminal member '7, so that theentire structure may pivot about the upper trunnions.

The upper contact 3 is provided with a threaded upper end which receivesthe cap or enlarged, flat-topped nut 8, against which a spring 10 bears,such spring when the fuse is in circuit closed or operative positionbearing upon a corner or edge of the enlarged, fiat-topped cap 8.Further, a contact spring of the brush type, as indicated at 11, iscarried by the upper terminal member '7 and bears against the uppercontact 3 at a point below the pivots 5, thereby tending to urge thefuse towards vertical position. It is preferable to so form the contact11 that it will follow the contact 3 outwardly substantially to avertical position of the fuse tube. This acts to prevent oscillation ofthe fuse tube after rupturing, and also tends to prevent the backwardswinging of the fuse when subjected to high wind pressure.

However, a further means for preventing oscillation of the fuse tubeafter blowing is afforded by the coaction of the spring 10 and thefiattopped cap or upper member 8. Obviously the spring in the positionshown in Figure 1 tends to urge the fuse tube towards vertical position.When this fuse tube rocks to vertical position, the approximatelyflattened lower portion 10' of the spring 10 bears against the flat topof the cap 8, and consequently this portion of the spring movesdownwardly and resists subsequent upward motion, thereby tending to holdor look the fuse tube in a substantially vertical position.

A support or bracket 12 may be provided for the entire device and maycarry an upper insulator 13 which carries the upper terminal member 7,and a lower insulator 14 which carries the lower terminal member 15. Thelower contact 4 of the fuse is engaged by a brush spring or lowercontact member 16 secured to the lower terminal member 5 and bearingagainst the lower contact 4 and urging the lower contact 4 of the fusetube out wardly. The lower contact member 4 may be provided with amanipulating ring 1'7 and may be received loosely between guides 18carried from the lower terminal member 15. The upper contact member 3may be provided with a. lip or tongue 18 adapted to be received in theslot of a fuse pole.

The lower contact member 4 pivotally supports a latching member 19 whichis provided with a flat face 20 bearing against the end of a lockingspring or lip 21. The member 21 may or may not be resilient, as desired,and also the members 19 and 21 may be formed induplicate on oppositesides of the fuse tube, if desired.

The latching member 19 is provided with a restraining arm 22 which isbeveled upwardly and which engages the beveled face of an car 23 formedon the fuse link plate 24. This fuse link plate is pivotally mounted, asindicated at 25, be-,

tween ears carried by the lower contact 4 of the fuse tube and is heldagainst outward swinging by looping a portion 26 of the fuse link aroundits lower'portion, the free end of the fuse link being clamped by meansof a screw or bolt 27, as indicated in the lower portion of Figure 1.'

If desired, the fuse link plate or lever 24 may have a bottom intumedportion 28 which i notched at its outer end to receive the inwardlybending portion of the fuse link, as shown in dotted lines at the lowerportion of Figure 1.

The upper end of the fuse link 26 may be provided with a disk orenlarged portion 29 which is clamped by the cap 8 against the upperportion of the contact 3, indicated in Figure 1.

When the fuse blows, the fuse link releases the fuse link plate or lever24 and the cammed portion 23 thereof rocks out of engagement with theportion 22, allowing the latch 19 to rock about its pivot and disengageitself from the restraining member 21. This permits the lower end of thefuse to swing outwardly under the double urge of the spring contacts 11and 16 as well as the spring 10, and also the urge of gravity.

As soon as the fuse tube swings outwardly to vertical position, theupper spring 10 bears against the flat top of the extended cap 8 andsubstantially locks the fuse in vertical position.

In addition to this, the spring 11 follows the upper contact 3 outwardlysubstantially to vertical position, and also aids in preventingoscillation of the fuse tube or inward motion of the fuse tube even whenacted upon by high wind pressure.

Thus both the members 10 and 11 cooperate, though the member 10 actssubstantially as a looking means to lock the fuse tube in verticalposition.

It is to be noted particularly that the fuse tube may be made as long asdesired, and consequent- 1y may be used for very high voltages, as thereis no shock upon the mechanism irrespective of the size or length of thefuse tube, due to the outward swinging of the fuse tube.

Further, it is clear that by spacing the upper supporting portionoutwardly from the lower supporting portion, it is possible to have thelower portion of the fuse tube swing outwardly from its lower contact.

Further, it will be seen that the device is of simple and reliableconstruction and is easy to produce.

Although this invention has been described in considerable detail, it isto be understood that 120 such description is intended as illustrativerather than limiting, as the invention may be variously embodied and isto be interpreted as claimed.

I claim:

1. A fuse comprising an upper terminal mem- 125 ber and a lower terminalmember, a fuse having upper and lower contacts electrically connected tosaid terminal members, said fuse being supported from said upperterminal member, releasable latching means temporarily holding the lowercontact in engagement with said lower terminal member, and a fuse linkjoining said upper and lower contacts and restraining said latchingmeans from opening movement, said upper terminal member being offsetwith respect to said lower terminal member, said fuse tending toswing bygravity away from said lower terminal member.

2. A fuse comprising an upper terminal member and a lower terminalmember set inwardly with respect to said upper terminal member, a fusehaving upper and lower contacts electrically connected to said terminalmembers, said fuse being supported from said upper terminal member,releasable latching means temporarily holding the lower contact inengagement with said lower terminal member, a fuse link joining saidupper and lower contacts and restraining said latching means fromopening movement, said fuse tending to swing by gravity outwardly away150 from said lower terminal member, and means tending to urge saidlower contact away from said lower terminal member.

3. A fuse comprising an upper terminal member and a lower terminalmember, a fuse having an upper and a lower contact, means pivotallyjoining the upper contact to said upper terminal member, said fusetending to swing'by gravity away from said lower terminal member, a fuselink electrically connecting said upper and lower contacts, and latchingmeans for temporarily holding said lower contact in electricalengagement with said lower terminal member, said latching means beingrestrained against opening motion by said fuse link.

4. A fuse comprising an upper terminal member and a lower terminalmember, a fuse having an upper contact pivotally connected to said upperterminal member and having a lower contact, a fuse link electricallyjoining said contacts, latching means including a member held by saidfuse link to prevent releasing motion of said latching means, saidlatching means temporarily holding said lower contact in electricalengagement with said lower terminal member, and spring contact meanstending to urge said lower contact outwardly from said lower terminalmem ber.

5. A fuse comprising an upper terminal member and a lower terminalmember, said upper terminal member being set outwardly with respect tosaid lower terminal member, a fuse pivotally supported from said upperterminal member and slanting inwardly and downwardly to said lowerterminal member, said fuse having an upper contact electricallyconnected to said upper terminal member and having a lower contacttemporarily electrically connected to said lower terminal member, a fuselink electrically joining said contacts, latching means temporarilyholding the lower contact in engagement with said lower terminal member,and means cooperating with said latching means and restraining theopening motion of said latching means, said means being connected tosaid fuse link whereby when said fuse link ruptures, said means isreleased, -thereby permitting said latching means to move to releasingposition, whereby the lower portion of said fuse swings outwardly fromsaid lower terminal member.

6. A fuse comprising an upper terminal member and a lower terminalmember, a fuse provided with an upper contact pivotally supported bysaid upper terminal member, said fuse having a lower contact normallyelectrically connected to said lower terminal member, said lowerterminal member being set inwardly with respect to said upper terminalmember, and said fuse being normally held in a downwardly and inwardlyslanting position, a fuse link joining said contacts, latching meansnormally holding said lower contact in electrical engagement with saidlower terminal member, said latching means being restrained againstopening motion by said fuse link, and means for preventing swinging ofsaid fuse after said fuse has blown and its lower end has rockedoutwardly from said lower terminal member.

'7. A fuse comprising an upper terminal member and a lower terminalmember, a fuse provided with an upper contact pivotally supported bysaid upper terminal member, said fuse having a lower contact normallyelectrically connected to said lower terminal member, said lowerterminal member being set inwardly with respect to said upper terminalmember, and said fuse being normally held in a downwardly and inwardlyslanting position, a fuse link joining said contacts, latching meansnormally holding said lower contact in electrical engagement with saidlower terminal member, said latching means being restrained againstopening motion by said fuse link, said fuse having a flat upper end anda spring supported from said upper terminal member and cooperating withsaid flat upper end to prevent swinging of said fuse after said fuse hasblown and has rocked outwardly away from said lower terminal member.

8. A fuse comprising upper and lower terminal members, a fuse pivotallysupported from said upper terminal member, said fuse comprising atubular body having upper and lower contacts normally electricallyconnected to said upper and 115 lower terminal members, a spring lipcarried by said lower terminal member, a catch pivoted to said lowercontact and slidable over said spring lip, said spring lip normallylocking said catch,

a lever mounted on the outer side of said tubular 120 body andreleasably holding said latch against releasing motion, and a fuse linkpassing outwardly through the lower end of said tubul'ar body andextending over the end of said lever and secured to said lever, saidfuse being biased 125 towards swinging motion away from said lowerterminal member.

ALWIN G. STEINMAYER.

